INF file v13.9 / 13.152.0.0000 from 2013-09-08

An INF file is a plain text file used by Microsoft Windows for installation of software and drivers. INF files are most commonly used for installing device drivers for hardware components.
The structure of an INF file is very similar to that of an INI file; it contains various sections that specify the files to be copied, changes to the registry, etc. All INF files contain a [version] section with a Signature value specifying the version of Windows that the INF file is meant for. The signature is commonly $CHICAGO$ (for Windows 9x) or $WINDOWS NT$ (for Windows NT/2K/XP/Vista/7/8) Most of the remaining sections are user-defined and contain information specific to the component being installed.
Source: Wikipedia: INF file.